We can't see enough of this receipt to work out whether the waiter, seemingly named Chris, got a tip as well as this lovely drawing from their customer. If they also got a tip, everything's great. If they didn't, they might be waiting a while to get any value out of it.
Whoever drew this is clearly a talented and creative artist, so it's possible they might become famous one day. If they do, this receipt could be worth hundreds or even thousands of dollars. We'd advise Chris to keep hold of it!